(Done at Institut Fur Hirnforschung, Zurich) 1) Using an acetylcholinesterase (AChE) staining method in the spinal cord of the weakly electric gymnotid Sternarchus albifrons two populations of spinal neurones were found. The peripheral neurones related to the spinal musculature showed a positive staining reaction. The neurones (electromotor neurones) related to the electric organ (consisting simply of axons of these cells) lay about the central canal of the spinal cord appeared to lack dendrites and were AChE negative. 2) Thin section and freeze-tech studies in the subfornical organ of neonatal kittens have shown gap junctions on neuritic filapodia as well as on processes with immature synapses. A new type of "belted" gap junction of large size was found between early ependymal elements. 3) A comprehensive atlas of the freeze-etch morphology of the vertebrate nervous system was prepared.